The present invention relates, in general, to a new and improved device and method for removing the edge of a laminated board which has a laminate veneer extending out from the top and/or bottom of the board. It more particularly relates to a device which automatically senses and cuts, with a laser, the edge of a laminated board which has a laminate veneer extended out from at least one surface of the board.
Recent environmental regulations and the depletion of old-growth forests have made it increasingly difficult and expensive to obtain high-quality lumber for use in wood products. One way to address the difficulty and expense of obtaining high-quality lumber is to use a veneer laminate. Veneered parts are created by affixing a higher-quality veneer, such as high-grade or clear wood or melamine, over a lower-quality core, such as medium density fiberboard (MDF), particleboard, plywood, laminated veneer lumber (LVL), or finger-jointed stock. Veneered laminates more efficiently utilize high-quality wood, reducing wood requirements and associated costs.
Manufacturing this veneered material requires several steps. After applying a laminate layer to the surface of a core, the edge of a laminated board may extend outward from the perimeter of one or both surfaces of the core. The overhanging laminate layer is undesirable, and is typically removed by striking the overhanging layer until it breaks closer to the edge of the core. This process often causes chipping of the veneer""s edges, which may cause injury to the production personnel and end user as they handle the sharp edges of the material. Installers typically do not use the full sheet of material if it has cracks in the veneer around the perimeter. Therefore, end users often view the edge of the material as a waste product. p Therefore, there is a need for a process of removing overhang material which is highly accurate in production implementation, and which may be efficiently integrated into material manufacture to lower costs and improve results.
The present invention provides a simple and inexpensive device to automatically sense and trim the edge of a laminated board which has a laminate veneer extended outward from the top and/or bottom of the board. The cutting device maintains a preset distance from the edge of the board and trims the overhanging veneer. This invention is especially useful when trimming an overhanging layer from any type of regular or irregular shaped board. The present invention has a further advantage of providing sufficient positioning accuracy and repeatability to create smooth edges over a variety of surfaces including circles, arcs, polygons, etc.
According to a preferred embodiment of the invention, the single and/or dual surface trimmer and automatic edge sensing device is carried out by the use of a laser that is controlled and guided so as to remove overhanging laminate material by directing laser beam energy at the junction of the board and the laminate. A laminated board that needs trimming is placed in the laser cutting area and centered for cutting. The laser trimmer is then activated and a cutting beam begins moving along the perimeter of the board while trimming the overhanging laminate.
A sensor provides a feedback signal allowing relative positioning of the workpiece with respect to the laser beam. In an alternative embodiment, the sensor may provide a feedback signal allowing relative positioning of the laser beam with respect to the workpiece. The sensor is capable of sensing the edge of any type of regular or irregular shaped board, (circle, arc, polygon, etc.). The sensor detects the edge of the board and adjusts itself to cut at the junction of the board and the veneer laminate layer.
The laser proceeds around the perimeter of the board, cutting the excess melamine laminate layer from the top and/or bottom edges of the board at the same time. If there are any curves in the perimeter of the board or if the board is not straight in the cutting area, the automatic edge sensor will move the cutting head closer or farther from the board to keep the proper preset distance from the perimeter of the board while creating a smooth cutting edge.
The workpiece may be fastened to a standard production table or, alternatively, the workpiece may be mounted for relative movement in a two-axis positioner table. A robotic arm can also be used to guide the laser beam source in the required pattern extending in two or three dimensions.
Many other features, advantages, and objects of the invention will become apparent to those versed in the art upon reference to the accompanying drawings and detailed description, in which preferred embodiments incorporating the principles of the invention are disclosed as illustrative examples.